Biogenetic-type synthesis of santonin, chrysanolide, dihydrochrysanolide, tulirinol, arbusculin-C, tanacetin, and artemin

The title compounds were synthesized from their possible biogenetic precursors through hydroperoxide intermediates generated by photo-oxygenation. This route for biological oxygenation may serve as a substitute to epoxidation. The ¹³C n.m.r. spectral assignments for all intermediates were made. Single-crystal X-ray analyses unequivocally established the 1S configuration in dihydrochrysanolide (14) and its hydroperoxy-analogue (12). lsomorphous crystals of (12) and (14) belong to the monoclinic system, space group P21 with a = 14.350(6), b = 5.882(3), c = 10.343(3) Å, β = 107.64(2)°, Z = 2, for (12), and a = 14.461(6), b = 5.887(3), c = 9.698(4) Å, β = 107.44(2)°, Z = 2, for (14). Least-squares refinement of atomic parameters converged to R 0.040 for (12) and 0.033 for (14) over 1 484 and 1 300 reflections, respectively, measured by diffractometer.

Duke Scholars

Author Andrew T. McPhail Chemistry